Add GULSceneDelegateSwizzler (#4524)

* Add GULSceneDelegateSwizzler

* Comments updated

* Fix build issue on xcode 10.*

* Remove empty methods

* Format

* Fix pr issues

* Format

* Fix build issue

* Fix build issue

* Fix build issue

* Reuse plist keys for scene delegate swizzler

* Add tests for the NSNotificationCenter related code

* Fix pr issues

* Make proxyOriginalSceneDelegate and isSceneDelegateProxyEnabled callable before ios 13

* Keep interceptors iOS 13+ only

* Revert "Make proxyOriginalSceneDelegate and isSceneDelegateProxyEnabled callable before ios 13"

This reverts commit 9927c06.

* Fix a issue when the header is compiled but the implementation is not

This reverts commit a316673.

* Format

* Reuse [GULAppDelegateSwizzler isAppDelegateProxyEnabled]

* Fix build issue

* Revert to last green build

* Reuse [GULAppDelegateSwizzler isAppDelegateProxyEnabled] and fix other comments

* Make proxyOriginalSceneDelegate callable before ios 13

* Fix pr issues

Author: renkelvin

Firebase/Auth/Source/Auth/FIRAuth.m

@@ -29,6 +29,7 @@
 #import <FirebaseCore/FIRLogger.h>
 #import <FirebaseCore/FIROptions.h>
 #import <GoogleUtilities/GULAppDelegateSwizzler.h>
+#import <GoogleUtilities/GULSceneDelegateSwizzler.h>
 #import <GoogleUtilities/GULAppEnvironmentUtil.h>
 
 #import "FIREmailPasswordAuthCredential.h"
@@ -384,7 +385,8 @@ - (nullable instancetype)initWithAPIKey:(NSString *)APIKey appName:(NSString *)a
     UIApplication *application = [applicationClass sharedApplication];
 
     [GULAppDelegateSwizzler proxyOriginalDelegateIncludingAPNSMethods];
-    #endif
+    [GULSceneDelegateSwizzler proxyOriginalSceneDelegate];
+    #endif // TARGET_OS_IOS
 
     // Continue with the rest of initialization in the work thread.
     __weak FIRAuth *weakSelf = self;
@@ -439,7 +441,12 @@ - (nullable instancetype)initWithAPIKey:(NSString *)APIKey appName:(NSString *)a
           appCredentialManager:strongSelf->_appCredentialManager];
 
       [GULAppDelegateSwizzler registerAppDelegateInterceptor:strongSelf];
-      #endif
+      #if ((TARGET_OS_IOS || TARGET_OS_TV) && (__IPHONE_OS_VERSION_MAX_ALLOWED >= 130000))
+        if (@available(iOS 13, tvos 13, *)) {
+        [GULSceneDelegateSwizzler registerSceneDelegateInterceptor:strongSelf];
+      }
+      #endif // ((TARGET_OS_IOS || TARGET_OS_TV) && (__IPHONE_OS_VERSION_MAX_ALLOWED >= 130000))
+      #endif // TARGET_OS_IOS
     });
   }
   return self;

GoogleUtilities.podspec

@@ -76,9 +76,9 @@ other Google CocoaPods. They're not intended for direct public usage.
   end
 
   s.subspec 'AppDelegateSwizzler' do |adss|
-    adss.source_files = 'GoogleUtilities/AppDelegateSwizzler/**/*.[mh]', 'GoogleUtilities/Common/*.h'
-    adss.public_header_files = 'GoogleUtilities/AppDelegateSwizzler/Private/*.h'
-    adss.private_header_files = 'GoogleUtilities/AppDelegateSwizzler/Private/*.h'
+    adss.source_files = 'GoogleUtilities/AppDelegateSwizzler/**/*.[mh]', 'GoogleUtilities/SceneDelegateSwizzler/**/*.[mh]', 'GoogleUtilities/Common/*.h'
+    adss.public_header_files = 'GoogleUtilities/AppDelegateSwizzler/Private/*.h', 'GoogleUtilities/SceneDelegateSwizzler/Private/*.h'
+    adss.private_header_files = 'GoogleUtilities/AppDelegateSwizzler/Private/*.h', 'GoogleUtilities/SceneDelegateSwizzler/Private/*.h'
     adss.dependency 'GoogleUtilities/Logger'
     adss.dependency 'GoogleUtilities/Network'
     adss.dependency 'GoogleUtilities/Environment'

GoogleUtilities/AppDelegateSwizzler/GULAppDelegateSwizzler.m

@@ -31,11 +31,6 @@ typedef BOOL (*GULRealOpenURLSourceApplicationAnnotationIMP)(
 typedef BOOL (*GULRealOpenURLOptionsIMP)(
     id, SEL, GULApplication *, NSURL *, NSDictionary<NSString *, id> *);
 
-#if UISCENE_SUPPORTED
-API_AVAILABLE(ios(13.0), tvos(13.0))
-typedef void (*GULOpenURLContextsIMP)(id, SEL, UIScene *, NSSet<UIOpenURLContext *> *);
-#endif  // UISCENE_SUPPORTED
-
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wstrict-prototypes"
 typedef void (*GULRealHandleEventsForBackgroundURLSessionIMP)(
@@ -80,11 +75,12 @@ typedef void (*GULRealDidReceiveRemoteNotificationWithCompletionIMP)(
 // Since Firebase SDKs also use this for app delegate proxying, in order to not be a breaking change
 // we disable App Delegate proxying when either of these two flags are set to NO.
 
-/** Plist key that allows Firebase developers to disable App Delegate Proxying. */
+/** Plist key that allows Firebase developers to disable App and Scene Delegate Proxying. */
 static NSString *const kGULFirebaseAppDelegateProxyEnabledPlistKey =
     @"FirebaseAppDelegateProxyEnabled";
 
-/** Plist key that allows developers not using Firebase to disable App Delegate Proxying. */
+/** Plist key that allows developers not using Firebase to disable App and Scene Delegate Proxying.
+ */
 static NSString *const kGULGoogleUtilitiesAppDelegateProxyEnabledPlistKey =
     @"GoogleUtilitiesAppDelegateProxyEnabled";
 
@@ -294,20 +290,6 @@ + (void)proxyOriginalDelegate {
     id<GULApplicationDelegate> originalDelegate =
         [GULAppDelegateSwizzler sharedApplication].delegate;
     [GULAppDelegateSwizzler proxyAppDelegate:originalDelegate];
-
-#if UISCENE_SUPPORTED
-    if (@available(iOS 13.0, tvOS 13.0, *)) {
-      if (![GULAppDelegateSwizzler isAppDelegateProxyEnabled]) {
-        return;
-      } else {
-        [[NSNotificationCenter defaultCenter]
-            addObserver:self
-               selector:@selector(handleSceneWillConnectToNotification:)
-                   name:UISceneWillConnectNotification
-                 object:nil];
-      }
-    }
-#endif  // UISCENE_SUPPORTED
   });
 }
 
@@ -703,17 +685,6 @@ + (void)notifyInterceptorsWithMethodSelector:(SEL)methodSelector
   }];
 }
 
-#if UISCENE_SUPPORTED
-+ (void)handleSceneWillConnectToNotification:(NSNotification *)notification {
-  if (@available(iOS 13.0, tvOS 13.0, *)) {
-    if ([notification.object isKindOfClass:[UIScene class]]) {
-      UIScene *scene = (UIScene *)notification.object;
-      [GULAppDelegateSwizzler proxySceneDelegateIfNeeded:scene];
-    }
-  }
-}
-#endif  // UISCENE_SUPPORTED
-
 // The methods below are donor methods which are added to the dynamic subclass of the App Delegate.
 // They are called within the scope of the real App Delegate so |self| does not refer to the
 // GULAppDelegateSwizzler instance but the real App Delegate instance.
@@ -793,36 +764,6 @@ - (BOOL)application:(GULApplication *)application
 
 #endif  // TARGET_OS_IOS
 
-#pragma mark - [Donor Methods] UISceneDelegate URL handler
-
-#if UISCENE_SUPPORTED
-- (void)scene:(UIScene *)scene
-    openURLContexts:(NSSet<UIOpenURLContext *> *)URLContexts API_AVAILABLE(ios(13.0), tvos(13.0)) {
-  if (@available(iOS 13.0, tvOS 13.0, *)) {
-    SEL methodSelector = @selector(scene:openURLContexts:);
-    // Call the real implementation if the real App Delegate has any.
-    NSValue *openURLContextsIMPPointer =
-        [GULAppDelegateSwizzler originalImplementationForSelector:methodSelector object:self];
-    GULOpenURLContextsIMP openURLContextsIMP = [openURLContextsIMPPointer pointerValue];
-
-    [GULAppDelegateSwizzler
-        notifyInterceptorsWithMethodSelector:methodSelector
-                                    callback:^(id<GULApplicationDelegate> interceptor) {
-                                      if ([interceptor
-                                              conformsToProtocol:@protocol(UISceneDelegate)]) {
-                                        id<UISceneDelegate> sceneInterceptor =
-                                            (id<UISceneDelegate>)interceptor;
-                                        [sceneInterceptor scene:scene openURLContexts:URLContexts];
-                                      }
-                                    }];
-
-    if (openURLContextsIMP) {
-      openURLContextsIMP(self, methodSelector, scene, URLContexts);
-    }
-  }
-}
-#endif  // UISCENE_SUPPORTED
-
 #pragma mark - [Donor Methods] Network overridden handler methods
 
 #if TARGET_OS_IOS || TARGET_OS_TV
@@ -1065,97 +1006,6 @@ + (void)proxyAppDelegate:(id<GULApplicationDelegate>)appDelegate {
   }
 }
 
-#if UISCENE_SUPPORTED
-+ (void)proxySceneDelegateIfNeeded:(UIScene *)scene {
-  Class realClass = [scene.delegate class];
-  NSString *className = NSStringFromClass(realClass);
-
-  // Skip proxying if failed to get the delegate class name for some reason (e.g. `delegate == nil`)
-  // or the class has a prefix of kGULAppDelegatePrefix, which means it has been proxied before.
-  if (className == nil || [className hasPrefix:kGULAppDelegatePrefix]) {
-    return;
-  }
-
-  NSString *classNameWithPrefix = [kGULAppDelegatePrefix stringByAppendingString:className];
-  NSString *newClassName =
-      [NSString stringWithFormat:@"%@-%@", classNameWithPrefix, [NSUUID UUID].UUIDString];
-
-  if (NSClassFromString(newClassName)) {
-    GULLogError(
-        kGULLoggerSwizzler, NO,
-        [NSString
-            stringWithFormat:@"I-SWZ%06ld",
-                             (long)kGULSwizzlerMessageCodeAppDelegateSwizzlingInvalidSceneDelegate],
-        @"Cannot create a proxy for Scene Delegate. Subclass already exists. Original Class"
-        @": %@, subclass: %@",
-        className, newClassName);
-    return;
-  }
-
-  // Register the new class as subclass of the real one. Do not allocate more than the real class
-  // size.
-  Class sceneDelegateSubClass = objc_allocateClassPair(realClass, newClassName.UTF8String, 0);
-  if (sceneDelegateSubClass == Nil) {
-    GULLogError(
-        kGULLoggerSwizzler, NO,
-        [NSString
-            stringWithFormat:@"I-SWZ%06ld",
-                             (long)kGULSwizzlerMessageCodeAppDelegateSwizzlingInvalidSceneDelegate],
-        @"Cannot create a proxy for Scene Delegate. Subclass already exists. Original Class"
-        @": %@, subclass: Nil",
-        className);
-    return;
-  }
-
-  NSMutableDictionary<NSString *, NSValue *> *realImplementationsBySelector =
-      [[NSMutableDictionary alloc] init];
-
-  // For scene:openURLContexts:
-  SEL openURLContextsSEL = @selector(scene:openURLContexts:);
-  [self proxyDestinationSelector:openURLContextsSEL
-      implementationsFromSourceSelector:openURLContextsSEL
-                              fromClass:[GULAppDelegateSwizzler class]
-                                toClass:sceneDelegateSubClass
-                              realClass:realClass
-       storeDestinationImplementationTo:realImplementationsBySelector];
-
-  // Store original implementations to a fake property of the original delegate.
-  objc_setAssociatedObject(scene.delegate, &kGULRealIMPBySelectorKey,
-                           [realImplementationsBySelector copy], OBJC_ASSOCIATION_RETAIN_NONATOMIC);
-  objc_setAssociatedObject(scene.delegate, &kGULRealClassKey, realClass,
-                           OBJC_ASSOCIATION_RETAIN_NONATOMIC);
-
-  // The subclass size has to be exactly the same size with the original class size. The subclass
-  // cannot have more ivars/properties than its superclass since it will cause an offset in memory
-  // that can lead to overwriting the isa of an object in the next frame.
-  if (class_getInstanceSize(realClass) != class_getInstanceSize(sceneDelegateSubClass)) {
-    GULLogError(
-        kGULLoggerSwizzler, NO,
-        [NSString
-            stringWithFormat:@"I-SWZ%06ld",
-                             (long)kGULSwizzlerMessageCodeAppDelegateSwizzlingInvalidSceneDelegate],
-        @"Cannot create subclass of Scene Delegate, because the created subclass is not the "
-        @"same size. %@",
-        className);
-    NSAssert(NO, @"Classes must be the same size to swizzle isa");
-    return;
-  }
-
-  // Make the newly created class to be the subclass of the real Scene Delegate class.
-  objc_registerClassPair(sceneDelegateSubClass);
-  if (object_setClass(scene.delegate, sceneDelegateSubClass)) {
-    GULLogDebug(
-        kGULLoggerSwizzler, NO,
-        [NSString
-            stringWithFormat:@"I-SWZ%06ld",
-                             (long)kGULSwizzlerMessageCodeAppDelegateSwizzlingInvalidSceneDelegate],
-        @"Successfully created Scene Delegate Proxy automatically. To disable the "
-        @"proxy, set the flag %@ to NO (Boolean) in the Info.plist",
-        [GULAppDelegateSwizzler correctAppDelegateProxyKey]);
-  }
-}
-#endif  // UISCENE_SUPPORTED
-
 #pragma mark - Methods to print correct debug logs
 
 + (NSString *)correctAppDelegateProxyKey {

GoogleUtilities/AppDelegateSwizzler/Internal/GULAppDelegateSwizzler_Private.h

@@ -18,10 +18,6 @@
 #import <GoogleUtilities/GULAppDelegateSwizzler.h>
 #import <GoogleUtilities/GULMutableDictionary.h>
 
-#if ((TARGET_OS_IOS || TARGET_OS_TV) && (__IPHONE_OS_VERSION_MAX_ALLOWED >= 130000))
-#define UISCENE_SUPPORTED 1
-#endif
-
 @class GULApplication;
 
 NS_ASSUME_NONNULL_BEGIN
@@ -54,17 +50,6 @@ NS_ASSUME_NONNULL_BEGIN
  */
 + (id<GULApplicationDelegate>)originalDelegate;
 
-#if UISCENE_SUPPORTED
-
-/** ISA Swizzles the given appDelegate as the original app delegate would be.
- *
- *  @param scene The scene whose delegate needs to be isa swizzled. This should conform to the
- *      scene delegate protocol.
- */
-+ (void)proxySceneDelegateIfNeeded:(UIScene *)scene API_AVAILABLE(ios(13.0), tvos(13.0));
-
-#endif  // UISCENE_SUPPORTED
-
 @end
 
 NS_ASSUME_NONNULL_END

GoogleUtilities/Common/GULLoggerCodes.h

@@ -18,22 +18,38 @@
 
 typedef NS_ENUM(NSInteger, GULSwizzlerMessageCode) {
   // App Delegate Swizzling.
-  kGULSwizzlerMessageCodeAppDelegateSwizzling000 = 1000,                   // I-SWZ001000
-  kGULSwizzlerMessageCodeAppDelegateSwizzling001 = 1001,                   // I-SWZ001001
-  kGULSwizzlerMessageCodeAppDelegateSwizzling002 = 1002,                   // I-SWZ001002
-  kGULSwizzlerMessageCodeAppDelegateSwizzling003 = 1003,                   // I-SWZ001003
-  kGULSwizzlerMessageCodeAppDelegateSwizzling004 = 1004,                   // I-SWZ001004
-  kGULSwizzlerMessageCodeAppDelegateSwizzling005 = 1005,                   // I-SWZ001005
-  kGULSwizzlerMessageCodeAppDelegateSwizzling006 = 1006,                   // I-SWZ001006
-  kGULSwizzlerMessageCodeAppDelegateSwizzling007 = 1007,                   // I-SWZ001007
-  kGULSwizzlerMessageCodeAppDelegateSwizzling008 = 1008,                   // I-SWZ001008
-  kGULSwizzlerMessageCodeAppDelegateSwizzling009 = 1009,                   // I-SWZ001009
-  kGULSwizzlerMessageCodeAppDelegateSwizzling010 = 1010,                   // I-SWZ001010
-  kGULSwizzlerMessageCodeAppDelegateSwizzling011 = 1011,                   // I-SWZ001011
-  kGULSwizzlerMessageCodeAppDelegateSwizzling012 = 1012,                   // I-SWZ001012
-  kGULSwizzlerMessageCodeAppDelegateSwizzling013 = 1013,                   // I-SWZ001013
-  kGULSwizzlerMessageCodeAppDelegateSwizzlingInvalidAppDelegate = 1014,    // I-SWZ001014
-  kGULSwizzlerMessageCodeAppDelegateSwizzlingInvalidSceneDelegate = 1015,  // I-SWZ001015
+  kGULSwizzlerMessageCodeAppDelegateSwizzling000 = 1000,                 // I-SWZ001000
+  kGULSwizzlerMessageCodeAppDelegateSwizzling001 = 1001,                 // I-SWZ001001
+  kGULSwizzlerMessageCodeAppDelegateSwizzling002 = 1002,                 // I-SWZ001002
+  kGULSwizzlerMessageCodeAppDelegateSwizzling003 = 1003,                 // I-SWZ001003
+  kGULSwizzlerMessageCodeAppDelegateSwizzling004 = 1004,                 // I-SWZ001004
+  kGULSwizzlerMessageCodeAppDelegateSwizzling005 = 1005,                 // I-SWZ001005
+  kGULSwizzlerMessageCodeAppDelegateSwizzling006 = 1006,                 // I-SWZ001006
+  kGULSwizzlerMessageCodeAppDelegateSwizzling007 = 1007,                 // I-SWZ001007
+  kGULSwizzlerMessageCodeAppDelegateSwizzling008 = 1008,                 // I-SWZ001008
+  kGULSwizzlerMessageCodeAppDelegateSwizzling009 = 1009,                 // I-SWZ001009
+  kGULSwizzlerMessageCodeAppDelegateSwizzling010 = 1010,                 // I-SWZ001010
+  kGULSwizzlerMessageCodeAppDelegateSwizzling011 = 1011,                 // I-SWZ001011
+  kGULSwizzlerMessageCodeAppDelegateSwizzling012 = 1012,                 // I-SWZ001012
+  kGULSwizzlerMessageCodeAppDelegateSwizzling013 = 1013,                 // I-SWZ001013
+  kGULSwizzlerMessageCodeAppDelegateSwizzlingInvalidAppDelegate = 1014,  // I-SWZ001014
+
+  // Scene Delegate Swizzling.
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling000 = 1100,                   // I-SWZ001100
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling001 = 1101,                   // I-SWZ001101
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling002 = 1102,                   // I-SWZ001102
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling003 = 1103,                   // I-SWZ001103
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling004 = 1104,                   // I-SWZ001104
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling005 = 1105,                   // I-SWZ001105
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling006 = 1106,                   // I-SWZ001106
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling007 = 1107,                   // I-SWZ001107
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling008 = 1108,                   // I-SWZ001108
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling009 = 1109,                   // I-SWZ001109
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling010 = 1110,                   // I-SWZ001110
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling011 = 1111,                   // I-SWZ001111
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling012 = 1112,                   // I-SWZ001112
+  kGULSwizzlerMessageCodeSceneDelegateSwizzling013 = 1113,                   // I-SWZ001113
+  kGULSwizzlerMessageCodeSceneDelegateSwizzlingInvalidSceneDelegate = 1114,  // I-SWZ001114
 
   // Method Swizzling.
   kGULSwizzlerMessageCodeMethodSwizzling000 = 2000,  // I-SWZ002000